AbstractDexterous space manipulators have proven to be a great asset, enabling in-space assembly and repair, assisting astronauts, and supporting experiments. Serial manipulators on the International Space Station are used to accomplish spacecraft berthing, and were instrumental in the assembly of the station itself. As technology improves, robotic systems are able to accomplish more complex tasks. The use of multiple cooperating robot systems will allow for greater strength, accuracy, and stiffness of payload motion; current plans use multiple dexterous manipulators to perform future tasks such as satellite servicing, refueling, and asteroid retrieval.

A multiarm system working cooperatively has multiple manipulators that interact with each other. Forces and torques applied to one arm are directly shared and distributed to the other arms, imposing a set of kinematic and dynamic constraints on the system. Payload transportation is one of the most commonly used examples of multiarm cooperation. Here, multiple manipulators work together to move an object which, conceptually, is beyond the capability of a single manipulator.

The focus of this paper takes a systems view on the benefits of multiple cooperating serial link manipulators, as compared to a single manipulator with independent movement. The overall system mass was chosen as the primary performance metric, as it is a critical design parameter for any system which will be a payload on a rocket and it allows systems to be compared even if manipulators of different lengths and degrees of freedom are used. Results indicate that sets of small arms can accomplish the same complex sets of tasks as single large serial manipulators, at significantly reduced mass and power levels. A system-level approach is presented for determining when multiarm complex systems are beneficial, along with analytical guidelines for selecting optimal multiarm configurations.

About the Robotics Graduate Student SeminarsThe Robotics Student Seminars at the University of Maryland College Park are a student-run series of talks given by current graduate and undergraduate students.

The purpose of these talks is to:

Encourage interaction between Robotics students from different subfields;

Provide an opportunity for Robotics students to be aware of and possibly get involved in the research their peers are conducting;

Provide an opportunity for Robotics students to receive feedback on their current research;